본 연구는 의료용 선형가속기 시설을 차폐하는 콘크리트에 대한 중성자 방사화 연구로써, 일반 콘크리트 와 저 방사화 콘크리트를 비교 분석하였다. 실험 방법은 MCNPX (Ver. 2.5.0)와 FISPACT-2010를 사용하여 모의실험을 진행하여, 광자선과 중성자선에 대한 차폐능을 산정하고 중성자 방사화 평가를 진행하였다. 그 결과 차폐능은 일반 콘크리트에서 20~50 ㎝ 효율적이였으며, 방사화 평가의 경우 저 방사화 콘크리트에서 방사능이 낮게 계산되었으나, 모두 자체처분허용 농도를 초과하지 않는 수준으로 산정되었다. 이를 종합적 으로 분석한 결과 일반 콘크리트를 사용하는 것이 효율적인 것으로 판단된다.

Background : Ginseng berry(GB) is useful not only just in growing source but also in functional food source. The ingredients of crops varies with the maturity. So, GB ingredients need to be analyse for optimal harvesting stage of GB against appropriate use. Methods and Results : This study was carried out to determine optimal harvesting stage of GB. GB was harvested 5 day periods from July 12, started harvesting when pollination was 50 days old, until August 1. GB was analysed color, ginsenosides and fatty acids using colorimeter, LC and GC, respectively. As the majority of GB increase, color of freeeze drying GB powder were changed that lightness and yellowness was increased, redness was decreased. Ginsenoside Re, Rb1 and Rb2, major ginsenoside in GB, were increased and Ginsenoside F1, Rk1 and Rg5, minor ginsenoside, were increased for a time and then decreased. Oleic acid, the main fatty acid in GB, was decreased, and linoleic acid and total fatty acid content was increased to July 27 and then decreased. Conclusion : Total ginsenosides content was the highest on August 1 and total fatty acid content was the highest July 27. As the majority of GB increase, ratio of oleic acid on total fatty acid was decreased and linoleic acid was increased. Thus, GB is that the longer a harvest period and the more useful for food source.